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Application of Short-wave Near-infrared Reflectance Spectroscopy in Controlling Extract of Fructus Cnidii Using Supercritical Carbon Dioxide 被引量:1
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作者 MI Hong GUO Ye +4 位作者 LI Wen-liang Qu Nan DOU Ying REN Yu-qiu REN Yu-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期116-119,共4页
Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharm... Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharmacological studies have revealed crude extracts or components isolated from fructus cnidii possess antiallergic, antipruritic, antidermatophytic, antibacterial, antifungal, and antiosteoporotic activities. Osthole and imperatorin are the major compounds present in shechuangzi. They are often used as standards for the evaluation of the quality of shechuangzi products. 展开更多
关键词 Fructus cnidii Supercfitical carbon dioxide Short-wave near-infrared diffuse reflectance spectrum Artificial neural network Degree of approximation
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Effects of Nanoparticle Size and Morphology on IR Diffuse Reflection Spectra
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作者 孔小东 ZHUMei-wu ZHENGJia-sheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第4期18-20,共3页
Two kinds of nanopowders were studied.One is NiFe 2O 4 spherical nanopowders which have different particle sizes.Another is ZnO nanopowders including two series of spherical particles and tetrapod nanowhiskers.Throu... Two kinds of nanopowders were studied.One is NiFe 2O 4 spherical nanopowders which have different particle sizes.Another is ZnO nanopowders including two series of spherical particles and tetrapod nanowhiskers.Through measuring the infrared diffuse reflection spectra of nanopowders,it can be found that the particle size and morphology affect the infrared diffuse reflection spectra.For the NiFe 2O 4 nanopowders the smaller the particle size,the larger the K-M value.And when the particle size is large enough,the effect of the particle size on infrared diffuse reflection spectra would disappear.For the ZnO nanopowders the effects of the particle size and morphology are more special.The effect of the particle sizes of tetrapod whisker nanopowders on infrared diffuse reflection spectra is more than that of spherical nanopowders. 展开更多
关键词 IR diffuse reflection spectrum NANOPOWDER SIZE MORPHOLOGY
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Multi-diffused Reflection Spectroscopy of Rare Earths Doped LaOCl Powder Samples and the Calculation of Quantum Efficiency
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作者 蒋雪茵 张志林 许少鸿 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第2期94-98,共5页
The excitation and emission spectra, the relaxation time of principal spectral lines and multi-diffused reflection spectra in LaOCl: Er, LaOCl: Ho powder samples were measured. The diffused absorption spectrum was der... The excitation and emission spectra, the relaxation time of principal spectral lines and multi-diffused reflection spectra in LaOCl: Er, LaOCl: Ho powder samples were measured. The diffused absorption spectrum was derived from the multi-diffused reflection spectrum. According to Judd-Ofelt theory,the intensity parameters, radiative transition probabilities and quantum efficiencies of luminescence emission were calculated. Then comparison with erbium and holmium doped floride glass and other matrices were made. 展开更多
关键词 Powdered material Multi-diffused reflection Diffused reflection absorption spectrum Quantum efficiency
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Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst
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作者 Ting Li Zhen-Yu Zhang +5 位作者 De-Cun Luo Bo-Yu Xu Rong-Jiang Zhang Ji-Long Yao Dan Li Tao Xie 《Nano Research》 SCIE EI CSCD 2024年第9期7945-7956,共12页
Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases emissions.However,designing advanced photo-thermal catalysts remains a rese... Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases emissions.However,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation reaction.In this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)methanation.The La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties characterizations.The partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)reduction.The catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)methanation.The results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)measurements.The in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen dissociation.More H^(*)spillover accelerated the rate-determining step(RDS)of HCOO*hydrogenation.This work provides the theoretical basis for the development of catalysts and industrial application. 展开更多
关键词 photo-thermal catalysis CO_(2)methanation PEROVSKITE A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)
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Candidate Biomarkers in Children with Autism Spectrum Disorder: A Review of MRI Studies 被引量:7
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作者 Dongyun Li Hans-Otto Karnath Xiu Xu 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第2期219-237,共19页
Searching for effective biomarkers is one of the most challenging tasks in the research ?eld of Autism Spectrum Disorder(ASD). Magnetic resonance imaging(MRI) provides a non-invasive and powerful tool for investi... Searching for effective biomarkers is one of the most challenging tasks in the research ?eld of Autism Spectrum Disorder(ASD). Magnetic resonance imaging(MRI) provides a non-invasive and powerful tool for investigating changes in the structure, function, maturation,connectivity, and metabolism of the brain of children with ASD. Here, we review the more recent MRI studies in young children with ASD, aiming to provide candidate biomarkers for the diagnosis of childhood ASD. The review covers structural imaging methods, diffusion tensor imaging, resting-state functional MRI, and magnetic resonance spectroscopy. Future advances in neuroimaging techniques, as well as cross-disciplinary studies and largescale collaborations will be needed for an integrated approach linking neuroimaging, genetics, and phenotypic data to allow the discovery of new, effective biomarkers. 展开更多
关键词 Autism spectrum disorder Biomarker Neuroimaging Structural MRI diffusion tensor imaging Resting-state functional MRI Magnetic resonance spectroscopy Children Human
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A Fiber Tractography Study of Social-Emotional Related Fiber Tracts in Children and Adolescents with Autism Spectrum Disorder 被引量:5
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作者 Yun Li Hui Fang +7 位作者 Wenming Zheng Lu Qian Yunhua Xiao Qiaorong Wu Chen Chang Chaoyong Xiao Kangkang Chu Xiaoyan Ke 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第6期722-730,共9页
The symptoms of autism spectrum disorder(ASD) have been hypothesized to be caused by changes in brain connectivity. From the clinical perspective, the‘‘disconnectivity'' hypothesis has been used to explain chara... The symptoms of autism spectrum disorder(ASD) have been hypothesized to be caused by changes in brain connectivity. From the clinical perspective, the‘‘disconnectivity'' hypothesis has been used to explain characteristic impairments in ‘‘socio-emotional'' function.Therefore, in this study we compared the facial emotional recognition(FER) feature and the integrity of socialemotional-related white-matter tracts between children and adolescents with high-functioning ASD(HFA) and their typically developing(TD) counterparts. The correlation between the two factors was explored to find out if impairment of the white-matter tracts is the neural basis of social-emotional disorders. Compared with the TD group,FER was significantly impaired and the fractional anisotropy value of the right cingulate fasciculus was increased in the HFA group(P / 0.01). In conclusion, the FER function of children and adolescents with HFA was impaired and the microstructure of the cingulate fasciculus had abnormalities. 展开更多
关键词 Autism spectrum disorder Facial emotional recognition Social-emotional related white matter fiber tracts diffusion tensor imaging Tractography
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